Successful reduction of morticians' exposure to formaldehyde during embalming procedures

A case study of the effectiveness of upgraded ventilation engineering controls in a military mortuary facility was performed. Worst-case mortician formaldehyde exposures generated during the use of highly concentrated embalming fluid (required to meet a 2-week preservation standard for overseas case processing and return of the deceased to the continental United States) were documented. A detailed exposure evaluation via consecutive short-term exposure limit (STEL) samples facilitated characterization of the hazard potential for each distinct phase of the embalming process. After baseline screening with 3M passive formaldehyde dosimeters, a total of 145 personal and area STEL sorbent tube samples were collected during six embalming cases between 1994 and 1998. Prior to the installation of local exhaust ventilation controls, personal time-weighted average (TWA) exposure values during embalming activities were 3.19-7.69 ppm for a mean of 4.80 ppm (calculated 8-hour TWA exposures for mortician workshifts were 1.32-2.86 ppm, mean 1.93 ppm). Initial STEL exposures ranged from a low of 0.14 during preembalming body preparation to 20.89 ppm during aspiration of arterial fluids (mean = 4.16 ppm). Embalming room general area samples revealed a mean concentration of 0.76 ppm. With ventilation upgrades installed in 1997, calculated personal 8-hour TWA exposure values during embalming procedures were reduced. STEL exposures decreased to between 0.11 to 3.44 ppm (mean of 0.55 ppm); embalming room general area sample concentrations decreased to a mean of 0.089 ppm. Because occasional 15-min peak exposures continued to exceed the 2.0 ppm Occupational Safety and Health Administration STEL during tasks involving large volumes of embalming fluid or direct contact with paraformaldehyde preservative powders, general room ventilation was further upgraded to 25 room air changes per hour.